(1) Field of the Invention
The present invention relates to a dose-indicator device and to a fluid or powder dispenser device including such a dose-indicator device.
(2) Description of Related Art
Dose-indicator devices are well known for indicating to the user the number of doses that have been emitted or that remain to be emitted from a fluid dispenser device, for example, such as a dry-powder inhaler or the like. Indicator devices must satisfy a certain number of requirements. Thus, they must be absolutely reliable, i.e. indicate each dose emitted, so as to avoid any risk of under-counting and/or of over-counting. They must also be suitable for counting any number of doses, in particular a relatively high number of doses, such as sixty doses, for example. In parallel, they must be as compact as possible, so as not to increase excessively the dimensions of the dispenser devices to which they are associated. Naturally, they must be simple and fairly easy to manufacture and to assemble. They must also provide an unambiguous and clearly visible indication of the doses that have been emitted or that remain to be emitted, e.g. through a viewing window provided in the indicator device. Known indicator devices generally present a certain number of drawbacks. A major drawback resides in the fact that while wishing to maintain an overall size that is as small as possible for the indicator device, it must be possible to count a large number of doses, e.g. sixty, which generally results in the indicator numbers or symbols that are to be read by the user being of very small size, with a risk that the user cannot clearly distinguish them, which can in particular be the situation when the user is an elderly person or a person with impaired vision. Depending on the kind of fluid or powder to be dispensed, it is essential for the user to be fully informed about the number of doses that have been emitted or that remain to be emitted, so as to avoid discovering that an appliance is empty during an attack that requires medication to be administered rapidly, for example. A wrong indication, or an indication that is not clearly legible, and that risks being misinterpreted by the user, therefore presents a risk.